The closure of incisions or lacerations in human skin has long been a need in the medical industry. Whether the incision is the result of surgeries such as cosmetic surgery or internal organ operations, or those generated by traumatic events or accidents, surgeons are continually presented with patients needing closure of such skin openings. For example, modern studies indicate that approximately 30 million such operations are performed each year in the U.S. alone.
In closing such incisions, surgeons are able to choose from a relatively limited number of options currently available. One of those options is manual suturing. This is perhaps the oldest of the available options and conventionally involves the physician directing a needle, to which is temporarily attached a suturing filament, through one section of skin, across the incision and into the other side of the incision. This process is repeated as many times as necessary to result in a certain number of “stitches” closing the incision. Upon reaching the end of the incision, the physician ties off the last suture to complete the process. While effective, manual suturing is certainly not without its drawbacks. For example, in the case of body contouring surgery, relatively large incisions in excess of many centimeters may be made which can often take the surgeon a very long time to close. It is not uncommon for the suturing of the incision to take longer than the actual operation itself. Not only is it time consuming, but surgeons often view the process as tedious. Moreover, the repeated movement of the needle through the skin of the patient necessarily increases the risk to the surgeon or assistant of being exposed to a needle prick which in turn can lead to certain transmissions of diseases including but not limited to Hepatitis C and HIV.
Given the time and difficulty involved with manual suturing, another closure option which is commonly employed is referred to as stapling. This process typically uses metal staples that are reminiscent of the staples commonly used in office settings to clip papers together. Specifically, stapling involves directing first and second parallel prongs of the staple into the first and second sections of skin to be connected, and against an anvil-like surface provided on the outside of the incision. When the prongs penetrate through the skin and contact the anvil, the prongs are deformed so as to be transverse to the main body of the staple and thus secured in position. The prongs are typically canted slightly inwardly so as to facilitate this deformation. The staples are installed using a medical device typically having some form of spring biased drive mechanism to quickly and effectively deploy the staples.
While significantly faster than manual suturing, staples themselves are also associated with certain drawbacks. Foremost among those drawbacks is the significant scarring associated with staples. The scarring is often referred to as “railroad tracks”, as the scar will typically include the linear incision itself laterally flanked by pairs of matching demarcations where the prongs of the staple enter the skin. Moreover, staples are significantly more painful to the patient in that they need to be removed after being installed and after the incision is healed. Suturing, on the other hand, can often be performed with absorbable sutures which disintegrate or are absorbed by the body after installation.
In light of the foregoing, a still further option currently available to surgeons is known as an absorbable dermal stapler wherein the staples are manufactured from a material or anchor which can be absorbed by the patient. One example of such an absorbable dermal stapler is marketed under the trademark “Insorb™”. This can potentially avoid a significant level of pain associated with metal staple removal, but may result in significant scarring or poor wound healing in general. This is due to: (a) less than optimal alignment associated with such absorbable staplers between the two sections of skin to be fastened; (b) poor wound holding strength which can result in areas of wound separation if there is any tension on the wound edges (tension which is not uncommon during the post-operative period) and; (c) and creation of small areas of wound separation where the thick fasteners extrude through the incision (known clinically as “spitting” of the fasteners). In order to most effectively close an incision with minimal scarring, it is advantageous to position the first and second sections of skin so as to both be within the same plane (vertical alignment), and to approximate the skin edges as close together as possible (horizontal alignment). If these sections of skin are not well approximated with regard to horizontal alignment, the resulting scar will be relatively wide as the body will fill in the gap with additional connective tissue. If the wound edges are not well aligned in the vertical dimension, then the scar will heal with a “step-off” which causes the scar to be more prominent.
Current absorbable dermal stapling technology provides less than optimal horizontal and vertical alignment. In addition to ensuring precise alignment of the superficial skin surface (epidermis), optimal wound closures should provide good approximation and support in the deeper strength-bearing layer of the skin (dermis). When the dermis is effectively secured, the wound forms a wound surface that is well aligned but slightly protrusive at the superficial surface, a desirable wound configuration that is clinically known as “eversion.” As the wound heals, the eversion gradually settles, resulting in a flat/optimal scar. The converse of eversion is wound inversion, which is characterized by the closed wound edges dipping inward. Inversion must be avoided in order to prevent the wound from forming a scar with a recessed valley appearance. Current dermal staplers attempt to position the wound in an everted fashion. However, the method in which the fasteners hold the wound edges in eversion results in prominent “dimpling” of the skin where the fasteners secure the skin edges, a closure appearance which can cause concern to surgeons when they try dermal staplers for wound closure.
With all these drawbacks in mind, a most recent effort has been made to provide a medical device which provides the fast and efficient closure afforded by staplers, with the decreased scarring associated with suturing. For example, U.S. Publication No. 2009/0093824 discloses a wound closure device which is adapted to position an anchor specifically known as an “H-Type” fastener between first and second sections of skin to be secured. The device includes channels in which the first and second sections of skin are to be positioned and includes a single arcuately shaped rotating needle adapted to enter one section of skin through the sub-dermal layer and carry the H-shaped anchor therewith. While the '824 application attempts to position the first and second sections of skin relative to one another, the use of such an H-shaped anchor does not adequately pull the two sections close together after insertion and thus would result in longer healing times and more scarring than is acceptable. More specifically, the leading prong of the “H” needs to be pulled entirely through the second section of skin in order to deploy. Once it is so deployed and released, the anchor is pulled back by the opposite prong and the normal tension on the wound edges, thus resulting in slack in the anchor and a loose “seam”. Moreover, the '824 application uses a complex system of rotating approximation arms to push the first and second sections of skin toward one another prior to insertion of the anchor. Not only does this make the device more complicated and expensive to manufacture and prone to reliability problems, but once the approximation arms are retracted so too are the sections of skin and again the resulting closure does not ensure optimal alignment, which would lead to prominent or otherwise poor scarring.